#### Answer

$ab^2c\sqrt{abc}$

#### Work Step by Step

$\sqrt{a^3b^5c^3}\longrightarrow$ factor out perfect square
=$\sqrt{a^2b^4c^2\times abc}\longrightarrow$ multiplication property of square roots
=$\sqrt{a^2b^4c^2}\times \sqrt {abc}\longrightarrow$ simplify
=$ab^2c\sqrt{abc}$